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author | Ulrich Drepper <drepper@redhat.com> | 1996-12-20 01:39:50 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 1996-12-20 01:39:50 +0000 |
commit | 6d52618b15cbe25ed4822ac51321db292f28ccda (patch) | |
tree | bafef072c0f5cb67c09d7c1789888d4310ac568f /sysdeps/libm-ieee754/e_log.c | |
parent | 10dc2a90b7f86d9bc1be9d1b9305a781882f7ac5 (diff) | |
download | glibc-6d52618b15cbe25ed4822ac51321db292f28ccda.tar.gz glibc-6d52618b15cbe25ed4822ac51321db292f28ccda.tar.xz glibc-6d52618b15cbe25ed4822ac51321db292f28ccda.zip |
Update from main archive 961219 cvs/libc-961220
Thu Dec 19 23:28:33 1996 Ulrich Drepper <drepper@cygnus.com> * resolv/resolv.h: Update from BIND 4.9.5-P1. * resolv/res_comp.c: Likewise. * resolv/res_debug.c: Likewise. * resolv/Banner: Update version number. Thu Dec 19 20:58:53 1996 Ulrich Drepper <drepper@cygnus.com> * elf/dlfcn.h: Add extern "C" wrapper. * io/utime.h: Don't define NULL since this isn't allowed in POSIX. * io/sys/stat.h: Declare `lstat' only if __USE_BSD || __USE_XOPEN_EXTENDED. * locale/locale.h: Define NULL. * math/math.c: Don't include <errno.h> to define math errors. * stdlib/stdlib.h: Likewise. * posix/unistd.h: Don't declare environ. * posix/sys/utsname.h (struct utsname): Declare member domainname as __domainname is !__USE_GNU. * signal/signal.h: Declare size_t only if __USE_BSD || __USE_XOPEN_EXTENDED. * stdio/stdio.h: Don't declare cuserid when __USE_POSIX, but instead when __USE_XOPEN. * string/string.h: Define strndup only if __USE_GNU. * sysdeps/unix/sysv/linux/clock.c: New file. * sysdeps/unix/sysv/linux/timebits.h: Define CLOCKS_PER_SEC as 1000000 per X/Open standard. * features.h: Add code to recognize _POSIX_C_SOURCE value 199309. Define __USE_POSIX199309. * posix/unistd.h: Declare fdatasync only if __USE_POSIX199309. * time/time.c: Declare nanosleep only if __USE_POSIX199309. Patches by Rüdiger Helsch <rh@unifix.de>. * locale/locale.h: Add declaration of newlocale and freelocale. * new-malloc/Makefile (distibute): Add mtrace.awk. (dist-routines): Add mcheck and mtrace. (install-lib, non-lib.a): Define as libmcheck.a. * new-malloc/malloc.h: Add declaration of __malloc_initialized. * new-malloc/mcheck.c: New file. * new-malloc/mcheck.h: New file. * new-malloc/mtrace.c: New file. * new-malloc/mtrace.awk: New file. * posix/unistd.h: Correct prototype for usleep. * sysdeps/unix/bsd/usleep.c: De-ANSI-declfy. Correct return type. * sysdeps/unix/sysv/linux/usleep.c: Real implementation based on nanosleep. * signal/signal.h: Change protoype of __sigpause to take two arguments. Remove prototype for sigpause. Add two different macros named sigpause selected when __USE_BSD or __USE_XOPEN are defined. This is necessary since the old BSD definition of theis function collides with the X/Open definition. * sysdeps/posix/sigpause.c: Change function definition to also fit X/Open definition. * sysdeps/libm-i387/e_exp.S: Make sure stack is empty when the function is left. * sysdeps/libm-i387/e_expl.S: Likewise. Patch by HJ Lu. 1996-12-17 Paul Eggert <eggert@twinsun.com> * many, many files: Spelling corrections. * catgets/catgetsinfo.h (mmapped): Renamed from mmaped (in struct catalog_info.status). * mach/err_kern.sub (err_codes_unix), string/stratcliff.c (main): Fix spelling in message. * po/libc.pot: Fix spelling in message for `zic'; this anticipates a fix in the tzcode distribution. Wed Dec 18 15:48:02 1996 Ulrich Drepper <drepper@cygnus.com> * time/strftime.c: Implement ^ flag to cause output be converted to use upper case characters. * time/zic.c: Update from ADO tzcode1996n. Wed Dec 18 14:29:24 1996 Erik Naggum <erik@naggum.no> * time/strftime.c (add): Don't change global `i' until all is over. Define NULL is not already defined. Tue Dec 17 09:49:03 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * libio/iovsprintf.c (_IO_vsprintf): Change `&sf' to `&sf._sbf._f' to avoid the need for a cast. * libio/iovsscanf.c (_IO_vsscanf): Likewise. * sunrpc/rpc/xdr.h: Add prototype for xdr_free.
Diffstat (limited to 'sysdeps/libm-ieee754/e_log.c')
-rw-r--r-- | sysdeps/libm-ieee754/e_log.c | 40 |
1 files changed, 20 insertions, 20 deletions
diff --git a/sysdeps/libm-ieee754/e_log.c b/sysdeps/libm-ieee754/e_log.c index c27e0a9d64..f584694686 100644 --- a/sysdeps/libm-ieee754/e_log.c +++ b/sysdeps/libm-ieee754/e_log.c @@ -5,7 +5,7 @@ * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice + * software is freely granted, provided that this notice * is preserved. * ==================================================== */ @@ -15,19 +15,19 @@ static char rcsid[] = "$NetBSD: e_log.c,v 1.8 1995/05/10 20:45:49 jtc Exp $"; #endif /* __ieee754_log(x) - * Return the logrithm of x + * Return the logarithm of x * - * Method : - * 1. Argument Reduction: find k and f such that - * x = 2^k * (1+f), + * Method : + * 1. Argument Reduction: find k and f such that + * x = 2^k * (1+f), * where sqrt(2)/2 < 1+f < sqrt(2) . * * 2. Approximation of log(1+f). * Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s) * = 2s + 2/3 s**3 + 2/5 s**5 + ....., * = 2s + s*R - * We use a special Reme algorithm on [0,0.1716] to generate - * a polynomial of degree 14 to approximate R The maximum error + * We use a special Reme algorithm on [0,0.1716] to generate + * a polynomial of degree 14 to approximate R The maximum error * of this polynomial approximation is bounded by 2**-58.45. In * other words, * 2 4 6 8 10 12 14 @@ -35,22 +35,22 @@ static char rcsid[] = "$NetBSD: e_log.c,v 1.8 1995/05/10 20:45:49 jtc Exp $"; * (the values of Lg1 to Lg7 are listed in the program) * and * | 2 14 | -58.45 - * | Lg1*s +...+Lg7*s - R(z) | <= 2 + * | Lg1*s +...+Lg7*s - R(z) | <= 2 * | | * Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2. * In order to guarantee error in log below 1ulp, we compute log * by * log(1+f) = f - s*(f - R) (if f is not too large) * log(1+f) = f - (hfsq - s*(hfsq+R)). (better accuracy) - * - * 3. Finally, log(x) = k*ln2 + log(1+f). + * + * 3. Finally, log(x) = k*ln2 + log(1+f). * = k*ln2_hi+(f-(hfsq-(s*(hfsq+R)+k*ln2_lo))) - * Here ln2 is split into two floating point number: + * Here ln2 is split into two floating point number: * ln2_hi + ln2_lo, * where n*ln2_hi is always exact for |n| < 2000. * * Special cases: - * log(x) is NaN with signal if x < 0 (including -INF) ; + * log(x) is NaN with signal if x < 0 (including -INF) ; * log(+INF) is +INF; log(0) is -INF with signal; * log(NaN) is that NaN with no signal. * @@ -59,9 +59,9 @@ static char rcsid[] = "$NetBSD: e_log.c,v 1.8 1995/05/10 20:45:49 jtc Exp $"; * 1 ulp (unit in the last place). * * Constants: - * The hexadecimal values are the intended ones for the following - * constants. The decimal values may be used, provided that the - * compiler will convert from decimal to binary accurately enough + * The hexadecimal values are the intended ones for the following + * constants. The decimal values may be used, provided that the + * compiler will convert from decimal to binary accurately enough * to produce the hexadecimal values shown. */ @@ -105,12 +105,12 @@ static double zero = 0.0; k=0; if (hx < 0x00100000) { /* x < 2**-1022 */ - if (((hx&0x7fffffff)|lx)==0) + if (((hx&0x7fffffff)|lx)==0) return -two54/zero; /* log(+-0)=-inf */ if (hx<0) return (x-x)/zero; /* log(-#) = NaN */ k -= 54; x *= two54; /* subnormal number, scale up x */ GET_HIGH_WORD(hx,x); - } + } if (hx >= 0x7ff00000) return x+x; k += (hx>>20)-1023; hx &= 0x000fffff; @@ -125,14 +125,14 @@ static double zero = 0.0; if(k==0) return f-R; else {dk=(double)k; return dk*ln2_hi-((R-dk*ln2_lo)-f);} } - s = f/(2.0+f); + s = f/(2.0+f); dk = (double)k; z = s*s; i = hx-0x6147a; w = z*z; j = 0x6b851-hx; - t1= w*(Lg2+w*(Lg4+w*Lg6)); - t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); + t1= w*(Lg2+w*(Lg4+w*Lg6)); + t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7))); i |= j; R = t2+t1; if(i>0) { |